Photocatalytic Reduction of CO2 by Bi-Based Semiconductor: A Review on Recent Progress

Photocatalytic reduction of CO2 into valuable solar fuels represents a promising strategy to address both energy crises and carbon emissions. Bismuth-based semiconductors have emerged as attractive visible-light-driven photocatalysts due to their suitable band structures, layered architectures, and tunable morphologies. This review systematically summarizes recent advances in Bi-based photocatalysts for CO2 photoreduction. First, the fundamental principles and key challenges of CO2 photoreduction are outlined. Subsequently, the structural and electronic characteristics of typical Bi-based materials, including Bi2O3, Bi2S3, Bi2MO6 (M = W; Mo), BiVO4, and BiOX (X = Cl; Br; I), are discussed. Emphasis is placed on design strategies to enhance photocatalytic performance, such as vacancy engineering, microstructure control, crystal facet engineering, heterojunction construction, cocatalyst loading, and their combinations. A comprehensive comparison of catalytic activities under various conditions is also provided. Finally, current limitations and future perspectives are highlighted, aiming to guide the rational design of efficient and stable Bi-based photocatalysts for CO2 conversion.